U.S. patent number 10,589,285 [Application Number 15/645,140] was granted by the patent office on 2020-03-17 for feeder breaker with reduced fines generation.
This patent grant is currently assigned to Joy Global Underground Mining LLC. The grantee listed for this patent is Joy MM Delaware, Inc.. Invention is credited to Charles M. Anderson, Jr., Michael Nolan.
United States Patent |
10,589,285 |
Anderson, Jr. , et
al. |
March 17, 2020 |
Feeder breaker with reduced fines generation
Abstract
A feeder breaker includes a frame, a first crusher coupled to
the frame and configured to receive material, a second crusher
coupled to the frame, a conveyor extending between the first
crusher and the second crusher configured to convey material
exiting the first crusher to the second crusher, and an output
conveyor configured to receive the material exiting the second
crusher. The feeder breaker is also configured to allow at least a
portion of material exiting the first crusher that is below a
predetermined size threshold to move to the output conveyor without
passing through the second crusher.
Inventors: |
Anderson, Jr.; Charles M.
(Paris, KY), Nolan; Michael (Lexington, KY) |
Applicant: |
Name |
City |
State |
Country |
Type |
Joy MM Delaware, Inc. |
Wilmington |
DE |
US |
|
|
Assignee: |
Joy Global Underground Mining
LLC (Warrendale, PA)
|
Family
ID: |
62909426 |
Appl.
No.: |
15/645,140 |
Filed: |
July 10, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20190009279 A1 |
Jan 10, 2019 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B02C
21/02 (20130101); E21F 13/002 (20130101); B02C
23/02 (20130101); B02C 23/16 (20130101); B02C
4/10 (20130101); B02C 23/08 (20130101) |
Current International
Class: |
B02C
21/02 (20060101); B02C 23/02 (20060101); E21F
13/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1941906 |
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3503640 |
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3503640 |
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1136130 |
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2924037 |
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FR |
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2929536 |
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2924037 |
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2186504 |
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H11347493 |
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|
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|
3778696 |
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May 2006 |
|
JP |
|
Other References
"Drag Chain Feeders & Feeder-Breaker", web page, 2016, 2 pages,
McLanahan, http://mclanahan.com/products/drag-
Chain-feeders-feeder-breakers/. cited by applicant .
GB1605286.2 Search Report from the United Kingdom Intellectual
Property Office dated Jul. 22, 2016 (3 pages). cited by applicant
.
European Patent Office Search Report for Application No.
18182621.5-1018 dated Dec. 10, 2018 (7 pages). cited by
applicant.
|
Primary Examiner: Katcoff; Matthew
Attorney, Agent or Firm: Michael Best & Friedrich
LLP
Claims
What is claimed is:
1. A feeder breaker comprising: a frame; a first crusher coupled to
the frame and configured to receive a material; a second crusher
coupled to the frame; a conveyor extending between the first
crusher and the second crusher, the conveyor configured to convey
the material exiting the first crusher to the second crusher; and
an output conveyor configured to receive the material exiting the
second crusher; wherein at least a portion of the material exiting
the first crusher that is below a predetermined size threshold
moves to the output conveyor without passing through the second
crusher, and wherein the output conveyor is positioned underneath
the second crusher.
2. The feeder breaker of claim 1, further comprising a
flow-limiting member positioned between the first crusher and the
second crusher, wherein the flow-limiting member is configured to
limit a flow of the material to the second crusher to below a flow
threshold.
3. The feeder breaker of claim 2, wherein the flow-limiting member
is a dam coupled to the frame.
4. The feeder breaker of claim 3, wherein the dam is coupled to the
frame above a portion of the conveyor and at an outlet of the first
crusher.
5. The feeder breaker of claim 2, wherein the flow-limiting member
further directs the material toward the conveyor.
6. The feeder breaker of claim 1, further comprising a feeder
coupled to the frame and configured to receive the material at a
material inlet, and wherein an inlet conveyor extends between the
material inlet and the first crusher.
7. The feeder breaker of claim 6, wherein the conveyor includes
slats through which some of the material that is below a second
predetermined size threshold moves to the output conveyor without
passing through the first crusher.
8. The feeder breaker of claim 7, wherein the output conveyor is
positioned underneath the slats, the first crusher, and the
conveyor.
9. The feeder breaker of claim 1, wherein the conveyor includes a
plurality of rotating shafts with a clearance between adjacent
rotating shafts.
10. The feeder breaker of claim 9, wherein the plurality of
rotating shafts are eccentrically-shaped.
11. The feeder breaker of claim 1, wherein the ratio of the size of
the material entering the first crusher and the size of the
material exiting the second crusher is 12:1.
12. A feeder breaker comprising: a frame having a first end, a
second end opposite the first end, and a material flow direction
defined between the first end and the second end; a conveying
assembly coupled to the frame and configured to convey a material
in the material flow direction; a first crusher coupled to the
frame and configured to receive the material conveyed by the
conveying assembly; a second crusher coupled to the frame
downstream of the first crusher in the material flow direction, the
second crusher is configured to receive the material conveyed by
the conveying assembly; and a flow-limiting member coupled to the
frame downstream of the first crusher in the material flow
direction; wherein the flow-limiting member is configured to limit
a flow of the material to the second crusher, and wherein the
flow-limiting member is a dam coupled to the frame above a portion
of the conveying assembly.
13. The feeder breaker of claim 12, wherein the flow-limiting
member further directs the flow of the material toward the
conveying assembly.
14. The feeder breaker of claim 12, wherein the flow-limiting
member is a first flow-limiting member and the feeder breaker
further includes a second flow-limiting member upstream of the
first crusher in the material flow direction.
15. The feeder breaker of claim 12, wherein the conveying assembly
includes an output conveyor and slats through which at least a
portion of the material below a predetermined size passes through a
conveyor section to the output conveyor.
16. The feeder breaker of claim 15, wherein the conveyor section is
positioned upstream of the first crusher.
17. The feeder breaker of claim 15, wherein the conveyor section is
positioned downstream of the first crusher.
18. The feeder breaker of claim 12, wherein the size of the
material downstream of the second crusher is at least 12 times
smaller than the size of the material upstream of the first
crusher.
19. A feeder breaker comprising: a frame; a first crusher coupled
to the frame, the first crusher including a first drum and a first
anvil; a second crusher coupled to the frame, the second crusher
including a second drum and a second anvil; and a conveyor
extending between the first crusher and the second crusher, wherein
the conveyor is configured to: (a) convey material through the
first crusher, between the first drum and the first anvil, (b)
convey the material exiting the first crusher to the second
crusher, and (c) convey the material through the second crusher,
between the second drum and the second anvil, and wherein at least
a portion of the material exiting the first crusher that is below a
predetermined size threshold bypasses the second crusher.
Description
FIELD OF THE INVENTION
The present invention relates to underground mining equipment, in
particular, a feeder breaker that reduces the amount of fines
generated while maintaining a large crushing ratio.
BACKGROUND OF THE INVENTION
Feeder breakers are generally used in mining applications to
appropriately size and sort a mine material. Typically, material
passes through feeder breakers and is broken down (e.g., crushed)
into a smaller size. However, the mine material may become too
small (i.e., fines), which is generally considered as waste.
SUMMARY OF THE INVENTION
In one embodiment, the invention provides a feeder breaker
including a frame, a first crusher coupled to the frame and
configured to receive a material, and a second crusher coupled to
the frame. The feeder breaker further includes a conveyor extending
between the first crusher and the second crusher. The conveyor is
configured to convey the material exiting the first crusher to the
second crusher. The feeder breaker further includes an output
conveyor configured to receive the material exiting the second
crusher. At least a portion of the material exiting the first
crusher that is below a predetermined size threshold moves to the
output conveyor without passing through the second crusher.
In another embodiment, the invention provides a feeder breaker
including a frame having a first end, a second end opposite the
first end, and a material flow direction defined between the first
end and the second end. The feeder breaker also includes a
conveying assembly coupled to the frame and configured to convey a
material in the material flow direction, a first crusher coupled to
the frame and configured to receive the material conveyed by the
conveying assembly, and a second crusher coupled to the frame
downstream of the first crusher in the material flow direction. The
second crusher is configured to receive the material conveyed by
the conveying assembly. The feeder breaker further includes a flow
limiting member coupled to the frame downstream of the first
crusher in the material flow direction. The flow-limiting member is
configured to limit a flow of the material to the second
crusher.
Other aspects of the invention will become apparent by
consideration of the detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a feeder breaker with partial
cross-section views shown according to an embodiment of the
invention.
FIG. 2 is a top view of the feeder breaker of FIG. 1 with partial
cross-sectional views shown.
FIG. 3 is a partial perspective view of the feeder breaker of FIG.
1, illustrating an inlet conveying section.
FIG. 4 is a partial perspective view of FIG. 3, with components
removed for clarity.
FIG. 5 is a partial perspective view of the feeder breaker of FIG.
1, illustrating a screening conveying section.
FIG. 6 is a partial perspective view of FIG. 5, with components
removed for clarity.
FIG. 7 is a cross sectional side view of the conveyor assembly of
FIG. 2, taken along lines 7-7.
FIG. 8 is a partial perspective view of the feeder breaker of FIG.
1, illustrating a flow limiting member.
FIG. 9 is a side view of the flow limiting member of FIG. 6.
FIG. 10 is a perspective view of the flow limiting member of FIG.
6.
FIG. 11 is a cross-sectional view of the feeder breaker of FIG. 1,
taken along lines 11-11 shown in of FIG. 1.
FIG. 12 is a side cross-sectional view of a feeder breaker with
partial cross-section views according to another embodiment of the
invention.
Before any embodiments of the invention are explained in detail, it
is to be understood that the invention is not limited in its
application to the details of construction and the arrangement of
components set forth in the following description or illustrated in
the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. It should be understood that the description of
specific embodiments is not intended to limit the disclosure from
covering all modifications, equivalents, and alternatives falling
within the spirit and scope of the disclosure. Also, it is to be
understood that the phraseology used herein for the purpose of
description and should not be regarded as limiting.
DETAILED DESCRIPTION
With reference to FIGS. 1-11, a feeder breaker 10 is illustrated
according to an embodiment of the invention. The feeder breaker 10
includes a frame 14, an input conveying section 18, a screening
conveying section 22, an output conveying assembly 26, a first
crusher 30, and a second crusher 34. The frame 14 includes supports
38 that support the feeder breaker 10 on a mine floor 42. The frame
14 has an intake end 46, a discharge end 50, a first lateral side
54, a second lateral side 58 opposite the first lateral side 54, a
top side 62, and a bottom side 66. Alternatively, the frame 14
includes crawlers, wheels, or other suitable mobile devices to
allow mobility of the feeder breaker 10. Additionally, the frame 14
includes a hopper 67 configured to receive material (e.g., from a
separate load, haul, dump (LHD) vehicle). In the illustrated
embodiment, the hopper 67 is a 3-way dump hopper. In other words,
the 3-way dump hopper allows material to be dumped in the hopper 67
from three different sides of the feeder breaker 10.
A material flow direction 68 is generally defined from the intake
end 46 of the frame 14 to the discharge end 50 of the frame 14. The
first crusher 30 and the second crusher 34 are coupled to the frame
14, with the first crusher 30 upstream in the material flow
direction 68 from the second crusher 34. Both the first crusher 30
and the second crusher 34 are configured to receive a material
(e.g., a mine material). The input conveying section 18 and the
screening conveying section 22 are subsequent in the material floor
direction 68 meaning mine material is conveyed from the input
conveying section 18 to the screening conveying section 22 from the
intake end 46 to the discharge end 50. A headshaft (drive shaft) 69
is located downstream of the second crusher 34 in the material flow
direction 68 and is coupled to the frame. A tailshaft 71 is also
coupled to the frame 14 upstream of the first crusher 30
approximate the intake end 46. The screening conveying section 22
is located between the first crusher 30 and the second crusher 34
to screen undersized material from the first crusher 34. The output
conveying assembly 26 is positioned beneath the input conveying
section 18 and the screening conveying section 22 and is configured
to convey appropriately sized mine material.
With reference to FIGS. 3-7, a conveyor 72 conveys material from
the intake end 46 to the discharge end 50 through both the input
conveyor section 18 and the screening conveyor section 22. The
conveyor 72 is coupled to the headshaft 69 and the tailshaft 71 and
is configured to travel in a continuous loop (i.e., continuous
conveyor). Travel of the conveyor 72 follows the continuous loop
from the tailshaft 71 to the headshaft 69, over the headshaft 69,
and back to the tailshaft. The conveyor 72 includes chains 74a and
74b (e.g., continuous chains) that are supported by wear strips
75a, 75b that extend in the material flow direction 68 between the
headshaft 69 and the tailshaft 71. Beneath the wear strips 75a, 75b
are beams 76 (e.g., I-beams) (FIG. 1) that extend from the first
side 54 of the frame 14 to the second side 58 of the frame 14. The
beams 76 are spaced apart to allow mine material under a
predetermined size to pass through. The beams 76 are also
positioned along the entire length of the frame 14 from the intake
end 46 to the discharge end 50 except for between the first crusher
30 and the second crusher 34.
Additionally, the conveyor 72 includes a plurality of flights 77
that links the chains 74a, 74b together. The flights 77 are
supported by slats 78 that extend in the material flow direction 68
from the headshaft 69 to the first crusher 30 and lay on top of the
beams 76 between the wear strips 75a, 75b. In the illustrated
embodiment, there are nine slats 78 each spaced apart from the
other by approximately 100 mm. In other embodiments, the number of
slats 78 can vary to accommodate mine material of different size to
pass. Each of the chains 74a, 74b and flights 77 are moveable
relative to the wear strips 75a, 75b, beams 76, and flights 77 by
the headshaft 69. In particular, the headshaft 69 is coupled to a
motor 79 and includes sprockets that each directly mesh with the
chains 74a, 74b.
With continued reference to FIGS. 3-7, a plurality of openings 80
are defined between the slats 78 and allow material smaller than a
first predetermined size (i.e., smaller than the openings 80) to
move through the beams 76 and onto the output conveying assembly 26
positioned below (FIG. 4). The openings 80 extend parallel to the
material flow direction 68 of the conveyor 72. In other
embodiments, the plurality of openings 80 may be any size to allow
for a particular size of material to pass through the plurality of
openings 80. The illustrated conveyor 72 is configured to allow
communication between the slats 78 and openings 80 and the output
conveying assembly 26 (FIG. 1) located below the conveyor 72.
With reference to FIGS. 1-4, the input conveying section 18 extends
between the hopper 67 and the first crusher 30 and is configured to
move material from the hopper 67 to the first crusher 30. In the
illustrated embodiment, the conveyor 72 is parallel to the mine
floor 42, but in alternative embodiments the input conveying
section 18 is oriented at an inclined angle relative to the mine
floor 42 from the hopper 67 towards the first crusher 30 to elevate
material from the hopper 67 in order to accommodate output
conveying assemblies 26 of different heights. Alternatively, the
supports 38 of the frame 14 may individually be height adjustable
to create an adjustable conveying angle with respect to the mine
floor 42 (e.g., an inclined or declined conveying path for mine
material). The input conveying section 18 includes an upstream end
82 positioned within the hopper 67, a downstream end 86 positioned
adjacent the first crusher 30, and a shield plate 90, to cover the
tailshaft 71.
With reference to FIGS. 1 and 10 the output conveying assembly 26
includes an output conveyor 102 and an integrated tailpiece 106
that supports and advances the output conveyor 102 (e.g., a
continuous conveyor system).
With reference to FIGS. 2 and 6, the first crusher 30 is operable
to reduce the size of material by a drive 130 rotating a crusher
drum 134 about a rotational axis A, in a clockwise direction as
viewed from FIG. 6. The crusher drum 134 and drive 130 are
supported on the frame 14 of the feeder breaker 10, with the
crusher drum 134 extending between the first lateral side 54 and
the second lateral side 58 of the frame 14. A first anvil 136 is
positioned under the first crusher drum 134 adjacent and downstream
from the plurality of slats 78 in the material flow direction 68.
The first anvil 136 provides support for material passed under the
first crusher. The crusher drum 34 includes a plurality of bits 138
(e.g., carbide bits) to directly contact and fracture material
supported on the first anvil 136. Material passes through the first
crusher 30 and onto the screening conveying section 22 through an
outlet 142 (FIG. 6). In the illustrated embodiment, material is
passed under the first crusher 30 to be fractured. In the
illustrated embodiment, the first crusher 30 has a sizing ratio
range between approximately 2:1 and approximately 10:1. In some
embodiments the sizing ratio of the first crusher 30 is 6:1. In
other words, the first crusher 30 fractures material that passes
through it to one sixth the original size of the material. In other
embodiments, the first crusher 30 could be configured to have a
different sizing ratio.
With reference to FIGS. 8-11, a flow limiting member 146 (e.g.,
flow limiting dam) is coupled to the top side 62 of the frame 14
and extends from the first lateral side 54 to the second lateral
side 58 of the frame 14. In the illustrated embodiment, the flow
limiting dam 146 is adjacent and downstream from the outlet 142 of
the first crusher 30. As described in greater detail below, the dam
146 limits the volumetric flow rate of material that is conveyed
from the first crusher 30 to the screening conveying section 22 and
limits the maximum height of the flow of material. In the
illustrated embodiment, the dam 146 has a polygonal cross section
and includes a back plate 150, a bottom plate 154, and a front
plate 158 having a forward edge 162. The dam 146 is mounted to the
frame 14 of the feeder breaker 10 by an upper mount 164, a first
side mount 165, and a second side mount 167. The upper mount 164
mounts the dam 146 to the top side 62 of the frame 14, the first
side mount 165 mounts the dam 146 to the first lateral side 54 of
the frame 14, and the second side mount, mounts the dam 146 to the
second lateral side 58 of the frame 14. Attached to the upper mount
164 of the dam 146, are crusher drum cleaning plates 163. The
cleaning plates 163 are positioned in between columns of bits 138
on the first crusher 30 to scrape off mine material that collects
between the columns of bits 128, which if not removed reduces the
efficiency of the first crusher 30. Each cleaning plate 163
protrudes from a front surface 169 of the upper mount and extends
from the top side 62 of the frame 14 over the front plate 158 and
proceeds pass the forward edge 162. In the illustrated embodiment,
there are six cleaning plates 163. In other embodiments, there can
be any number of cleaning plates 163.
Material is transferred from the first crusher 30, to the outlet
142 and onto the screening conveying section 22, where the material
flow is limited by the dam 146. A clearance 166 (FIG. 9) is defined
between the screening conveying section 22 and the bottom plate 154
of the dam 146 to allow a predetermined height of material flow to
pass through the dam 146 and continue onto the second crusher 34.
By limiting the height of the material flow, the dam 146 also
controls the volumetric flow rate of material. The clearance 166 is
adjustable and can be changed by adjusting the position of the
bottom plate 154 of the dam 146 with respect to the screening
conveying section 22. Material that exceeds the clearance 166 abuts
the front plate 158 of the dam 146 until the previously passed
material is transferred away from the dam 146, along the screening
conveying section 22 to the second crusher 34. Material moving
downstream of the dam 146 allows room for material upstream of the
dam 146 to pass through the clearance 166 towards the second
crusher 34. In alternative embodiments, the flow limiting member
is, for example, a gate with vertical bars or horizontal columns or
other suitable structure for limiting the flow of material. In
further alternative embodiments, the feeder breaker 10 includes a
second flow limiting member positioned in the material flow path
(e.g., upstream of the first crusher 30 in the material flow
direction 68).
With reference to FIGS. 5 and 6, the screening conveying section 22
extends between the first crusher 30 and the second crusher 34, and
is configured to screen undersized material that passes from the
outlet 142 of the first crusher 30 to the second crusher 34. The
screening conveying section 22 includes the conveyor 72 and a
plurality of rotating elliptical shafts 170. The rotating
elliptical shafts 170 are attached to the frame 14, and extend from
the first lateral side 54 of the frame 14 to the second lateral
side 58 of the frame 14 (i.e., a wobbler deck). Similar to the
slats 78 and openings 80 of the conveyor 72, material is also
screened through the screening conveying section 22 via the
plurality of rotating elliptical shafts 170.
With continued reference to FIGS. 5 and 6, the elliptical shafts
170 are positioned below the chains 74a, 74b, similar to the beams
76, within the continuous loop of the conveyor. In this embodiment,
the elliptical shafts 170 extend a length 174 (FIG. 1) between the
first crusher 30 and the second crusher 34 of the screening
conveying section 22 in the material flow direction 68. In other
embodiments, the elliptical shafts 170 extend for at least a
portion of the length 174 between the first crusher 30 and the
second crusher 34. The rotating elliptical shafts 170 are driven by
the motor 79 to rotate the shafts 170 the same direction, directing
material onto the output conveyor assembly 26. Each elliptical
shaft 170 is rotationally offset from an adjacent elliptical shaft
170 by 90 degrees in order to create a gap 178 between two adjacent
elliptical shafts 170. In the illustrated embodiment, the gap 178
of the elliptical shafts 170 allows materials between approximately
0 millimeters and approximately 100 millimeters to pass through and
onto the output conveyor 102. In some embodiments, the gap 178 is
in a range from approximately 50 millimeters to approximately 150
millimeters.
The gaps 178 allow material below a second predetermined size
(i.e., the gap size) to pass through the gaps 178 and onto the
output conveyor 102 while the screening conveyor section 22
transfers material above a second predetermined size to the second
crusher 34. In some embodiments, the second predetermined size is
equal to the first predetermined size. In other words, the
screening conveying section 22 moves material exiting the first
crusher 30 downstream in the material flow direction 68 and removes
material below the second predetermined size from the crushing flow
of material (i.e., the main flow of material from the input
conveying section 18 through the first crusher 30 and through the
second crusher 34). In this way, the amount of material that is
already appropriately sized is limited from passing through the
second crusher 34, which avoids generating additional unwanted
fines.
With reference to FIGS. 1 and 2, the second crusher 34 operates
much in the same way as the first crusher 30. The second crusher 34
is operable to reduce the size of material received after the
screening conveying section 22. Specifically, the second crusher 34
includes a drive 182 that rotates a crusher drum 186 about a
rotational axis B, in a clockwise direction as viewed from FIG. 1.
A second anvil 188 is positioned under the second crusher 34
crusher drum 134 adjacent and downstream from the elliptical shafts
178 in the material flow direction 68. The second anvil 188
provides support for material passed under the first crusher. The
crusher drum 186 has a plurality of bits 138 that directly contact
and fracture material supported on the second anvil 188 that passes
the crusher drum 186. Material that passes the second crusher 34
exits through an outlet 194 (FIG. 1) of the second crusher 34 to
pass over the discharge end 50 of the frame 14 and onto the output
conveying assembly 26. In the illustrated embodiment, the second
crusher 34 has a sizing ratio within a range of approximately 3:2
and approximately 4:1. In some embodiments the sizing ratio of the
second crusher 34 is approximately 2:1. In other words, material
that passes through the second crusher 34 is reduced in size by one
half.
In operation, the input conveying section 18, the screening
conveying section 22, the output conveyor assembly 26, the first
crusher 30, and the second crusher 34 operate to minimize the
generation of fines (i.e., material small enough that it is
generally considered waste). Fines, for example, are generally
defined as material less than 6 mm in diameter in many underground
mining applications. Fines are more likely to be created when
material of appropriate size passes through a crusher, reducing the
size of the already appropriately-sized material.
Material is initially received (e.g., dumped) into the input
conveying section 18 and collected within the hopper 67. As the
chains 74a, 74b continuously move along the conveyor wear strips
75a, 75b, the flights 77 push material received in the hopper 67
towards the first crusher 30. When the material passes over the
slats 78 and the openings 80, the flights 77 continue to push
material larger than the first predetermined size over the openings
80 with at least a portion of the material smaller than the first
predetermine size falling through the openings 80 and onto the
output conveyor 102 positioned below. Stated another way, material
is moved along the conveyor 72 by the flights 77 and at least a
portion of the material below the first predetermined size falls
through the openings without further traveling towards the first
crusher 30. Material larger than the openings 80 pass over the
slats 78 and openings 80 and is fed into the first crusher 30 to be
reduced before continuing onto the screening conveying section 22.
In this way, the fines generated by the first crusher 30 are
reduced since at least a portion of the material already below the
first predetermined size does not pass through the first crusher
30. Allowing material already below the first predetermined size to
pass through the openings 80, avoids passing correctly sized and/or
undersized material through the first crusher 30, which creates
more undersized material and fines (i.e., waste material).
With reference to FIGS. 1 and 9, operation continues with material
exiting the outlet 142 of the first crusher 30 where the material
is received by the screening conveying section 22. The dam 146
impedes the flow of material on the screening conveying section 22
to limit the amount of material that flows downstream of the dam
146. Specifically, the forward edge 162 of the front plate 158 of
the dam 146 funnels material downward along the front plate 158
toward the bottom plate 154 of the dam 146 (and toward the
screening conveying section 22) and, material will pass under the
dam 146 through the clearance 166 until the material flow height
exceeds the clearance 166. The excess material is blocked by the
dam 146 to control the flow of material, until there is enough room
for the excess material to be funneled under the dam 146 and
through the clearance 166. In addition to the flights 77 of the
conveyor 72, the plurality of elliptical shafts 170 helps pass the
material through the screening conveyor section 22. The plurality
of elliptical shafts 170 of the screening conveying section 22
rotate in a counter-clockwise direction as material is conveyed
from one elliptical shaft 170 to a downstream elliptical shaft 170.
Due to the elliptical shafts 170 being rotationally offset by 90
degrees, material will be sifted as the flights 77 move material
through the screening conveying section 22. When material passes
over elliptical shafts 170 with the long ends perpendicular to the
material flow direction 68, the material will experience an upward
push. When materials passes over an elliptical shaft with its long
end parallel to the material flow direction 68, material will
experience a drop. The continual push and drop will sift the
material as it passes over adjacent elliptical shafts 170 allowing
material under the second predetermined size to fall through the
gaps 178 and material over the second predetermined size to
continue onto the second crusher. Stated another way, material is
moved along the screening conveying section 22 by the rotating
elliptical shafts 170 and the conveyor 72 and at least a portion of
the material that is below the second predetermined size after
passing the first crusher 30 falls through the gaps 178 between the
shafts 170 and onto the output conveyor 102 without further
travelling towards the second crusher 34. The material larger than
the gaps 178 is transferred on the screening conveying section 22
to pass through the second crusher 34. The second crusher 34
reduces the size of material even further and exits the material
through the outlet portion 192 of the second crusher 34. Material
exiting the second crusher 34 is then transferred over the
discharge end 50 of the frame 14 and onto the output conveyor 102
where it is joined with material that has previously fallen on the
output conveying assembly 26 through either the openings 80 or the
gaps 178 of the screening conveying section 22. In other words, the
output conveyor 102 is configured to receive the material exiting
the second crusher 34.
The first crusher 30, the second crusher 34, the input conveying
section 18, and the screening conveying section 22 are controlled
by a controller (not shown) specifically to reduce the generation
of fines. In particular, the chains 74a, 74b are rotationally
driven by the headshaft 69 and the motor 79 to create a variable
material feed rate entering the first crusher 30. Similarly, the
elliptical shafts 170 are controlled by the motor 79 to create a
variable material feed rate entering the second crusher 34. In
addition, the crusher drums 134, 186 are controlled at variable
speeds by the drive 130, 182 (i.e., variable speed breaker drums).
In order to minimize wear and to reduce fines generation, the
rotational velocity of the crusher drums 134, 186 is controlled to
suit the velocity of the material passing through the crushers 30,
34. In other words, by varying the speed of the input conveying
section 18 and the crusher drums 134, 186, fines generation is
minimized.
The feeder breaker 10 with the first crusher 30, the second crusher
34, the input conveying section 18, the screening conveying section
22, and the output conveying assembly 26 allows for at least a
portion of the material under the first predetermined size not to
pass through the first crusher 30 and allows for at least a portion
of the material under the second predetermined size not to pass
through the second crusher 34, advantageously minimizing the
generation of fines. In other words, the amount of waste material
generated by the feeder breaker 10 is reduced. Additionally, the
feeder breaker 10 is advantageous in providing an overall crushing
ratio range of approximately 10:1 to approximately 14:1. In some
embodiments the crushing ratio is 12:1. The large overall crushing
ratio allows for large material to be quickly and efficiently
reduced to a desired size. Material normally too big for crushing
in a single industrial machine can now be reduced in size by going
through the feeder breaker 10, with reduced additional fines.
With reference to FIG. 12, a feeder breaker 210 is illustrated
according to another embodiment of the invention. The feeder
breaker 210 differs from the feeder breaker 10 in that the feeder
breaker 210 does not include a hopper (similar to the hopper 67),
but instead includes a flat input conveyor 198 that brings material
from a first end 246 of a frame 214 to a first crusher 230.
The feeder breaker 10 may also include a feeder portion coupled to
the intake end 46 of the frame 14. In other embodiments, the input
conveying section 18 and the screening conveying section 22 may be
interchangeable with each other. In further embodiments, the frame
14 may only have one continuous conveying assembly that transports
materials from the intake end 46 to the discharge end 50. This
continuous conveying assembly may include features of the input
conveying section 18 and/or the screening conveying section 22.
Additionally, the output conveyor 102 may be a belt conveyor or any
other type of conveyor.
Various features and advantages of the invention are set forth in
the following claims.
* * * * *
References